The present invention relates to a vehicle occupant protection system. More particularly, the present invention relates to a four-point seat belt system having retractors that are lockable by the vehicle occupant.
A known seat belt system includes two shoulder belts and two lap belts. Each shoulder belt extends from an associated shoulder belt retractor, which is fixed relative to an upper portion of a vehicle seat, downward to a buckle assembly. One lap belt extends upwardly from an anchor on the right side of the vehicle seat and through the buckle assembly. The lap belt then extends downwardly from the buckle assembly to a lap belt retractor. The other lap belt extends upwardly from an anchor on the left side of the vehicle seat and through the buckle assembly. The other lap belt then extends downwardly from the buckle assembly to the lap belt retractor.
The lap belt retractor includes a rewind spring for removing slack from the lap belts and a locking mechanism that prevents further withdrawal of the lap belts in response to a vehicle crash sensor detecting a crash event condition. Similarly, the shoulder belt retractors include rewind springs for removing slack from the shoulder belts and locking mechanisms that prevent further withdrawal of the shoulder belts in response to the vehicle crash sensor detecting a crash event condition. At times other than during a detected crash event condition, the lap belt retractor and the shoulder belt retractors enable the lap belts and the shoulder belts to be withdrawn.
During certain events, a vehicle occupant may desire to lock or cinch the lap belts and shoulder belts. For example, a driver of a four-wheel drive vehicle may occasionally desire to drive the vehicle off-road. During such occasions, the driver may want to lock the belts of the seat belt system to prevent withdrawal of the respective belts. As a result of preventing withdrawal of the respective belts, the driver is more securely retained in position on the vehicle seat.
The present invention relates to a vehicle occupant protection system. The vehicle occupant protection system comprises first and second lap belts. The first lap belt is for extending across a first lap portion of the vehicle occupant and the second lap belt is for extending across a second lap portion of the vehicle occupant. At least one lap belt retractor is operatively connected to the first and second lap belts and is electrically actuatable, in response to receiving a first electrical locking signal, for locking the at least one lap belt retractor to prevent withdrawal of the first and second lap belts. The vehicle occupant protection system also comprises first and second shoulder belts. The first shoulder belt is for extending over a first shoulder of the vehicle occupant and the second shoulder belt is for extending over a second shoulder of the vehicle occupant. A buckle assembly is provided for interconnecting the first and second shoulder belts and the first and second lap belts. An occupant actuatable mechanism is operatively connected to the at least one lap belt retractor and is responsive to actuation by the vehicle occupant for providing the first electrical locking signal to the at least one lap belt retractor.
According to another aspect, the present invention relates to a vehicle occupant protection system comprising first and second lap belts. The first lap belt is for extending across a first lap portion of the vehicle occupant and the second lap belt is for extending across a second lap portion of the vehicle occupant. At least one lap belt retractor is operatively connected to the first and second lap belts and is electrically actuatable, in response to receiving a first electrical locking signal, for locking the at least one lap belt retractor to prevent withdrawal of the first and second lap belts. The vehicle occupant protection system also comprises first and second shoulder belts. The first shoulder belt is for extending over a first shoulder of the vehicle occupant and the second shoulder belt is for extending over a second shoulder of the vehicle occupant. A buckle assembly interconnects the first and second shoulder belts and the first and second lap belts. An occupant actuatable switch has an off position and a first on position. The occupant actuatable switch, when in the first on position, provides the first electrical locking signal to the at least one lap belt retractor. The vehicle occupant protection system further comprises a crash sensor for detecting a crash event condition and for providing the first electrical locking signal to the at least one lap belt retractor when the occupant actuatable switch is in the off position and a crash event condition is detected.